Section 440.23. Nitric acid plants.

 

(1)   Applicability and designation of affected facility.

(a) The provisions of this section are applicable to each nitric acid production unit, which is the affected facility.

(b) Any facility under par. (a) that commences construction or modification after August 17, 1971, is subject to the requirements of this section.

(2)   Definitions. As used in this section, terms not defined in this subsection have the meanings given in s. NR 440.02 .

(a) "Nitric acid production unit" means any facility producing weak nitric acid by either the pressure or atmospheric pressure process.

(b) "Weak nitric acid" means acid which is 30 to 70% in strength.

(3)   Standard for nitrogen oxides.

(a) On and after the date on which the performance test required to be conducted by s. NR 440.08 is completed, no owner or operator subject to the provisions of this section may cause to be discharged into the atmosphere from any affected facility any gases which:

1. Contain nitrogen oxides, expressed as NO 2 , in excess of 1.5 kg per metric ton of acid produced (3.0 lb per ton), the production being expressed as 100% nitric acid.

2. Exhibit 10% opacity, or greater.

(4)   Emission monitoring.

(a) The source owner or operator shall install, calibrate, maintain and operate a continuous monitoring system for measuring nitrogen oxides (NO x ). The pollutant gas mixtures under Performance Specification 2 of Appendix B of 40 CFR part 60 , incorporated by reference in s. NR 440.17 , and for calibration checks under s. NR 440.13 (4) shall be nitrogen dioxide (NO 2 ). The span value shall be 500 ppm of NO 2 . Method 7 shall be used for the performance evaluation under s. NR 440.13 (3) . Acceptable alternative methods to Method 7 are given in sub. (5) (c) .

(b) The owner or operator shall establish a conversion factor for the purpose of converting monitoring data into units of the applicable standard (kg/metric ton, lb/ton). The conversion factor shall be established by measuring emissions with the continuous monitoring system concurrent with measuring emissions with the applicable reference method tests. Using only that portion of the continuous monitoring emission data that represents emission measurements concurrent with the reference method test periods, the conversion factor shall be determined by dividing the reference method test data averages by the monitoring data averages to obtain a ratio expressed in units of the applicable standard to units of the monitoring data, i.e., kg/metric ton per ppm (lb/ton per ppm). The conversion factor shall be reestablished during any performance test under s. NR 440.08 or any continuous monitoring system performance evaluation under s. NR 440.13 (3) .

(c) The owner or operator shall record the daily production rate and hours of operation.

(e) For the purpose of reports required under s. NR 440.07 (3) , periods of excess emissions that shall be reported are defined as any 3-hour period during which the average nitrogen oxides emissions (arithmetic average of 3 contiguous one-hour periods) as measured by a continuous monitoring system exceed the standard under sub. (3) (a) .

(5)   Test methods and procedures.

(a) In conducting the performance tests required in s. NR 440.08 , the owner or operator shall use as reference methods and procedures the test methods in Appendix A of 40 CFR part 60 , incorporated by reference in s. NR 440.17 , or other methods and procedures as specified in this subsection, except as provided in s. NR 440.08 (2) . Acceptable alternative methods and procedures are given in par. (c) .

(b) The owner or operator shall determine compliance with the NO x standard in sub. (3) as follows:

1. The emission rate (E) of NO x shall be computed for each run using the following equation:

E = (C s Q sd )/(PK)

where:

E is the emission rate of NO x as NO 2 , kg/metric ton (lb/ton) of 100% nitric acid

C s is the concentration of NO x as NO 2 , g/dscm (lb/dscf)

Q sd is the volumetric flow rate of effluent gas, dscm/hr (dscf/hr)

P is the acid production rate, metric ton/hr (ton/hr) or 100% nitric acid

K is the conversion factor, 1000 g/kg (1.0 lb/lb)

2. Method 7 shall be used to determine the NO x concentration of each grab sample. Method 1 shall be used to select the sampling site and the sampling point shall be the centroid of the stack or duct or at a point no closer to the walls than 1 m (3.28 ft). Four grab samples shall be taken at approximately 15-minute intervals. The arithmetic mean of the 4 sample concentrations shall constitute the run value (C s ).

3. Method 2 shall be used to determine the volumetric flow rate (Q sd ) of the effluent gas. The measurement site shall be the same as for the NO x sample. A velocity traverse shall be made once per run within the hour that the NO x samples are taken.

4. The methods of sub. (4) (c) shall be used to determine the production rate (P) of 100% nitric acid for each run. Material balance over the production system shall be used to confirm the production rate.

(c) The owner or operator may use the following as alternatives to the methods and procedures specified in this subsection:

1. For Method 7, Method 7A, 7B, 7C or 7D may be used. If Method 7C or 7D is used, the sampling time shall be at least 1 hour.

(d) The owner or operator shall use the procedure in sub. (4) (b) to determine the conversion factor for converting the monitoring data to the units of the standard.

History: Cr. Register, January, 1984, No. 337 , eff. 2-1-84; am. (4) (a), (5) (a) 1., and (b), Register, September, 1986, No. 369 , eff. 10-1-86; am. (2) (intro.), (4) (e) and (5) (b), Register, September, 1990, No. 417 , eff. 10-1-90; r. and recr. (4) (a) and (5), am. (4) (b), Register, June, 1993, No. 450 , eff. 8-1-93.